Add the ability to easily copy existing FlatMenus via the Wagtail adm…

…in area (#49)

* Use custom `clean()` method to raise useful ValidationError when unique_together isn't respected
* Adds FlatMenuCopyView to allow copying of an existing FlatMenu
* Adds 'copy' button to listing page to easily access for each FlatMenu

* Added a `link_handle` to `MenuItem` model (#39) (#41)

* Added a `link_handle` to `MenuItem` model (#39)
* Added documentation
* Added entries /credits to CHANGELOG.md and CONTRIBUTORS.md
* Improved consistency of 'new line usage'  in release notes
* Update screenshot of flat menu listing
* Added documentation
* Add `django-webtest` to test requirements and use to do some testing of the copy view

CHANGELOG.md

@@ -10,6 +10,13 @@ Changelog
   allow flat menus defined for the default site to be used as fall-backs, in
   cases where the 'current' site doesn't have its own menus set up with the
   specified handle.
+* Added a custom ValidationError to FlatMenu's `clean()` method that better
+  handles the `unique_together` rule that applied to `site` and `handle`
+  fields.
+* Added the ability to copy/duplicate existing FlatMenu objects between sites
+  (or to the same site with a different handle) via Wagtail's admin area. The
+  'Copy' button appears in the listing for anyone with 'add' permission, and
+  the view allows the user to make changes before anything is saved. 
 * Apply `active` classes to menu items that link to custom URLs (if
   `request.path` and `link_url` are exact matches).
 * Added a `handle` to `MenuItem` model to provide a string which can be 

README.md

@@ -22,6 +22,8 @@ Have you ever hard-coded a menu into a footer at the start of a project, only fo
 
 Flat menus are designed for outputting simple, flat lists of links, but they CAN be made to display multiple levels of pages too. See the instructions below for [using the `{% flat_menu %}` tag](#flat_menu-tag).
 
+In a multi-site project, you can choose to define a new set of menus for each site, or you can define one set of menus for your default site and reuse them for your other sites, or use a combination of both approaches for different menus (see the **`fall_back_to_default_site_menus`** option in [**Using the `{% flat_menu %}` tag**](#flat_menu-tag) to find out more). However you choose to do things, a 'copy' feature makes it easy to copy existing flat menus from one site to another via Wagtail's admin interface.
+
 ### 3. Offers a solution to the issue of key page links becoming 'toggles' in multi-level drop-down menus
 
 Extend the `wagtailmenus.models.MenuPage` model instead of the usual `wagtail.wagtailcore.models.Page` to create your custom page types, and gain a couple of extra fields that will allow you to configure certain pages to appear again alongside their children in multi-level menus. Use the menu tags provided, and that behaviour will remain consistent in all menus throughout your site.
@@ -89,11 +91,13 @@ Since version `1.2`, watailmenus has depended on the `wagtail.contrib.modeladmin
 ### <a id="defining-flat-menus"></a>2. Defining flat menus in the CMS
 
 1. Log into the Wagtail CMS for your project (as a superuser).
-2. Click on `Settings` in the side menu to access the options in there, then select `Flat menus`.
+2. Click on `Settings` in the side menu to access the options in there, then select `Flat menus` to access the menu list page.
 3. Click the button at the top of the page to add a flat menu for your site (or one for each of your sites if you are running a multi-site setup). <img alt="Screenshot showing the FlatMenu edit interface" src="https://raw.githubusercontent.com/rkhleics/wagtailmenus/master/screenshots/wagtailmenus-flatmenu-edit.png" />
 4. Fill out the form, choosing a 'unique for site' `handle` to reference in your templates.
 5. Use the **MENU ITEMS** inline panel to define the links you want the menu to have. If you wish, you can use the `handle` field to specify an additional value for each item, which you'll be able to access in a custom flat menu template. **NOTE**: Pages need to be published and have the `show_in_menus` checkbox checked in order to appear in menus (look under the **Promote** tab when editing pages).
-6. Save your changes to apply them to your site. 
+6. Save your changes to apply them to your site.
+
+All of the flat menus created for a project will appear in the menu list page (from step 2, above) making it easy to find, update, copy or delete your menus later. As soon as you create menus for more than one site in a multi-site project, the listing page will give you additional information and filters to help manage your menus, like so: <img alt="Screenshot showing the FlatMenu listing page for a multi-site setup" src="https://raw.githubusercontent.com/rkhleics/wagtailmenus/master/screenshots/wagtailmenus-flatmenu-list.png" />
 
 ### <a id="main_menu-tag"></a>3. Using the `{% main_menu %}` tag
 

requirements/testing.txt

@@ -1,5 +1,6 @@
 -r base.txt
 
+django-webtest>=1.8.0
 beautifulsoup4>=4.4.1,<4.5.0
 coverage>=3.6
 tox

tox.ini

@@ -19,6 +19,7 @@ basepython =
 deps =
     coverage>=3.6
     beautifulsoup4>=4.4.1,<4.5.0
+    django-webtest>=1.8.0
     dj18: Django>=1.8.1,<1.9
     dj19: Django>=1.9,<1.10
     dj110: Django>=1.10a1,<1.11

wagtailmenus/models.py

@@ -240,12 +240,27 @@ def get_for_site(cls, handle, site,
     def __str__(self):
         return '%s (%s)' % (self.title, self.handle)
 
+    def clean(self, *args, **kwargs):
+        # Raise validation error for unique_together constraint, as it's not
+        # currently handled properly by wagtail
+        clashes = FlatMenu.objects.filter(site=self.site, handle=self.handle)
+        if self.pk:
+            clashes = clashes.exclude(pk__exact=self.pk)
+        if clashes.count():
+            msg = _("Site and handle must create a unique combination. A menu "
+                    "already exists with these same two values.")
+            raise ValidationError({
+                'site': [msg],
+                'handle': [msg],
+            })
+        super(FlatMenu, self).clean(*args, **kwargs)
+
     panels = (
         MultiFieldPanel(
             heading=_("Settings"),
             children=(
-                FieldPanel('site'),
                 FieldPanel('title'),
+                FieldPanel('site'),
                 FieldPanel('handle'),
                 FieldPanel('heading'),
             )

wagtailmenus/settings/testing.py

@@ -1,6 +1,6 @@
 from .base import *  # NOQA
 
-DEBUG = True
+DEBUG = False
 SITE_ID = 1
 
 DATABASES = {

wagtailmenus/templates/wagtailmenus/flatmenu_copy.html

@@ -0,0 +1,4 @@
+{% extends "modeladmin/create.html" %}
+{% load i18n %}
+
+{% block form_action %}{{ view.copy_url }}{% endblock %}

wagtailmenus/tests/test_backend.py

@@ -3,14 +3,77 @@
 from django.contrib.auth import get_user_model
 from django.contrib.auth.models import Group
 from django.test import TransactionTestCase
+from django_webtest import WebTest
 from wagtail.wagtailcore.models import Site
+from wagtailmenus.models import FlatMenu
+
+
+class CMSUsecaseTests(WebTest):
+
+    # optional: we want some initial data to be able to login
+    fixtures = ['test.json']
+
+    def test_copy_footer_menu(self):
+        get_user_model().objects._create_user(
+            username='test1', email='test1@email.com', password='password',
+            is_staff=True, is_superuser=True)
+
+        site_one = Site.objects.get(id=1)
+        site_two = Site.objects.get(id=2)
+
+        # Start by getting the footer menu for site one
+        site_one_footer_menu = FlatMenu.get_for_site('footer', site_one)
+        copy_view = self.app.get(
+            '/admin/wagtailmenus/flatmenu/copy/%s/' % site_one_footer_menu.pk,
+            user='test1')
+
+        form = copy_view.forms[1]
+        form['site'] = site_two.pk
+        response = form.submit().follow()
+
+        assert len(response.context['object_list']) == 3
+        assert '<div class="changelist-filter col3">' in response
+
+        # Let's just compare the two menu with the old one
+        site_two_footer_menu = FlatMenu.get_for_site('footer', site_two)
+
+        assert site_one_footer_menu.pk != site_two_footer_menu.pk
+        assert site_one_footer_menu.heading == site_two_footer_menu.heading
+        assert site_one_footer_menu.menu_items.count() == site_two_footer_menu.menu_items.count()
+
+    def test_cannot_copy_footer_menu(self):
+        get_user_model().objects._create_user(
+            username='test1', email='test1@email.com', password='password',
+            is_staff=True, is_superuser=True)
+
+        site_one = Site.objects.get(id=1)
+        site_two = Site.objects.get(id=2)
+        # Start by getting the footer menu for site one
+        site_one_footer_menu = FlatMenu.get_for_site('footer', site_one)
+        # Create a new menu from the above one, for site two
+        site_two_footer_menu = site_one_footer_menu
+        site_two_footer_menu.id = None
+        site_two_footer_menu.site = site_two
+        site_two_footer_menu.save()
+        # Refetche menu one
+        site_one_footer_menu = FlatMenu.get_for_site('footer', site_one)
+
+        copy_view = self.app.get(
+            '/admin/wagtailmenus/flatmenu/copy/%s/' % site_one_footer_menu.pk,
+            user='test1')
+        form = copy_view.forms[1]
+        form['site'] = site_two.pk
+        response = form.submit()
+
+        assert 'The flat menu could not be saved due to errors' in response
+        assert 'Site and handle must create a unique combination.' in response
 
 
 class TestSuperUser(TransactionTestCase):
     fixtures = ['test.json']
 
     def setUp(self):
-        user = get_user_model().objects._create_user(
+        get_user_model().objects._create_user(
             username='test1', email='test1@email.com', password='password',
             is_staff=True, is_superuser=True)
         self.client.login(username='test1', password='password')
@@ -63,12 +126,48 @@ def test_mainmenu_edit_multisite(self):
     def test_flatmenu_list(self):
         response = self.client.get('/admin/wagtailmenus/flatmenu/')
         self.assertEqual(response.status_code, 200)
+        self.assertNotContains(
+            response, '<th scope="col"  class="sortable column-site">')
+        self.assertNotContains(response,
+                               '<div class="changelist-filter col3">')
+
+    def test_flatmenu_list_multisite(self):
+        site_one = Site.objects.get(id=1)
+        site_two = Site.objects.get(id=2)
+
+        # Start by getting the footer menu for site one
+        site_one_footer_menu = FlatMenu.get_for_site('footer', site_one)
+
+        # Use menu one to create another for site two
+        site_two_footer_menu = site_one_footer_menu
+        site_two_footer_menu.site = site_two
+        site_two_footer_menu.id = None
+        site_two_footer_menu.save()
+
+        # Redefine menu one, so that we definitely have two menus
+        site_one_footer_menu = FlatMenu.get_for_site('footer', site_one)
+
+        # Check the menus aren't the same
+        self.assertNotEqual(site_one_footer_menu, site_two_footer_menu)
+
+        # Check that the listing has changed to include the site column and
+        # filters
+        response = self.client.get('/admin/wagtailmenus/flatmenu/')
+        self.assertEqual(response.status_code, 200)
+        self.assertContains(
+            response, '<th scope="col"  class="sortable column-site">')
+        self.assertContains(response, '<div class="changelist-filter col3">')
 
     def test_flatmenu_edit(self):
         response = self.client.get(
             '/admin/wagtailmenus/flatmenu/edit/1/')
         self.assertEqual(response.status_code, 200)
 
+    def test_flatmenu_copy(self):
+        response = self.client.get(
+            '/admin/wagtailmenus/flatmenu/copy/1/')
+        self.assertEqual(response.status_code, 200)
+
 
 class TestNonSuperUser(TransactionTestCase):
     fixtures = ['perms.json', 'test.json']

wagtailmenus/views.py

@@ -1,4 +1,5 @@
 from __future__ import absolute_import, unicode_literals
+from copy import copy
 
 from django import forms
 from django.utils.text import capfirst
@@ -10,8 +11,8 @@
 from wagtail.wagtailadmin import messages
 from wagtail.wagtailcore.models import Site
 
-from wagtail.contrib.modeladmin.views import WMABaseView, ModelFormView
-from .models import MainMenu
+from wagtail.contrib.modeladmin.views import (
+    WMABaseView, EditView, ModelFormView)
 
 
 class SiteSwitchForm(forms.Form):
@@ -51,7 +52,7 @@ def __init__(self, model_admin, instance_pk):
         self.site = get_object_or_404(Site, id=self.instance_pk)
         self.edit_url = self.model_admin.url_helper.get_action_url(
             'edit', self.instance_pk)
-        self.instance = MainMenu.get_for_site(self.site)
+        self.instance = self.model.get_for_site(self.site)
         self.instance.save()
 
     def get_meta_title(self):
@@ -94,3 +95,44 @@ def get_error_message(self):
 
     def get_template_names(self):
         return ['wagtailmenus/mainmenu_edit.html']
+
+
+class FlatMenuCopyView(EditView):
+    page_title = _('Copying')
+
+    @property
+    def copy_url(self):
+        return self.url_helper.get_action_url('copy', self.pk_quoted)
+
+    def get_meta_title(self):
+        return _('Copying %s') % self.opts.verbose_name
+
+    def check_action_permitted(self, user):
+        return self.permission_helper.user_can_create(user)
+
+    def get_form_kwargs(self):
+        kwargs = super(FlatMenuCopyView, self).get_form_kwargs()
+        """
+        When the form is posted, don't pass an instance to the form. It should
+        create a new one out of the posted data. We also need to nullify any
+        IDs posted for inline menu items, so that new instances of those are
+        created too.
+        """
+        if self.request.method == 'POST':
+            data = copy(self.request.POST)
+            i = 0
+            while(data.get('menu_items-%s-id' % i)):
+                data['menu_items-%s-id' % i] = None
+                i += 1
+            kwargs.update({
+                'data': data,
+                'instance': self.model()
+            })
+        return kwargs
+
+    def get_success_message(self, instance):
+        return _("{model_name} '{instance}' created.").format(
+            model_name=capfirst(self.opts.verbose_name), instance=instance)
+
+    def get_template_names(self):
+        return ['wagtailmenus/flatmenu_copy.html']

wagtailmenus/wagtail_hooks.py

@@ -1,14 +1,17 @@
 from django.conf.urls import url
+from django.contrib.admin.utils import quote
 from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext_lazy as _
 
 from wagtail.contrib.modeladmin.options import ModelAdmin, modeladmin_register
+from wagtail.contrib.modeladmin.helpers import ButtonHelper
 from wagtail.wagtailcore import hooks
 
 from .app_settings import (
     MAINMENU_MENU_ICON, FLATMENU_MENU_ICON, SECTION_ROOT_DEPTH)
 from .models import MainMenu, FlatMenu
-from .views import MainMenuIndexView, MainMenuEditView
+from .views import (
+    MainMenuIndexView, MainMenuEditView, FlatMenuCopyView)
 
 
 class MainMenuAdmin(ModelAdmin):
@@ -32,23 +35,59 @@ def get_admin_urls_for_registration(self):
 modeladmin_register(MainMenuAdmin)
 
 
+class FlatMenuButtonHelper(ButtonHelper):
+
+    def copy_button(self, pk, classnames_add=[], classnames_exclude=[]):
+        cn = self.finalise_classname(classnames_add, classnames_exclude)
+        return {
+            'url': self.url_helper.get_action_url('copy', quote(pk)),
+            'label': _('Copy'),
+            'classname': cn,
+            'title': _('Copy this %s') % self.verbose_name,
+        }
+
+    def get_buttons_for_obj(self, obj, exclude=[], classnames_add=[],
+                            classnames_exclude=[]):
+        ph = self.permission_helper
+        usr = self.request.user
+        pk = quote(getattr(obj, self.opts.pk.attname))
+        btns = super(FlatMenuButtonHelper, self).get_buttons_for_obj(
+            obj, exclude, classnames_add, classnames_exclude)
+        if('copy' not in exclude and ph.user_can_create(usr)):
+            btns.append(
+                self.copy_button(pk, classnames_add, classnames_exclude)
+            )
+        return btns
+
+
 class FlatMenuAdmin(ModelAdmin):
     model = FlatMenu
     menu_label = _('Flat menus')
     menu_icon = FLATMENU_MENU_ICON
+    button_helper_class = FlatMenuButtonHelper
     ordering = ('-site__is_default_site', 'site__hostname', 'handle')
     add_to_settings_menu = True
 
-    def is_multisite(self, request):
-        return self.get_queryset(request).values('site').distinct().count() > 1
+    def copy_view(self, request, instance_pk):
+        kwargs = {'model_admin': self, 'instance_pk': instance_pk}
+        return FlatMenuCopyView.as_view(**kwargs)(request)
+
+    def get_admin_urls_for_registration(self):
+        urls = super(FlatMenuAdmin, self).get_admin_urls_for_registration()
+        urls += (
+            url(self.url_helper.get_action_url_pattern('copy'),
+                self.copy_view,
+                name=self.url_helper.get_action_url_name('copy')),
+        )
+        return urls
 
     def get_list_filter(self, request):
-        if self.is_multisite(request):
+        if self.is_multisite_listing(request):
             return ('site', 'handle')
         return ()
 
     def get_list_display(self, request):
-        if self.is_multisite(request):
+        if self.is_multisite_listing(request):
             return ('title', 'handle_formatted', 'site', 'items')
         return ('title', 'handle_formatted', 'items')
 
@@ -57,6 +96,9 @@ def handle_formatted(self, obj):
     handle_formatted.short_description = 'handle'
     handle_formatted.admin_order_field = 'handle'
 
+    def is_multisite_listing(self, request):
+        return self.get_queryset(request).values('site').distinct().count() > 1
+
     def items(self, obj):
         return obj.menu_items.count()
     items.short_description = _('no. of items')